Valgus ankle deformity is associated with increased mechanical complications and revision following total ankle arthroplasty.

BACKGROUND

Coronal plane deformities of the ankle, including varus and valgus malalignment, present technical challenges in total ankle arthroplasty (TAA) and may affect implant performance, although their impact on short-term outcomes remains uncertain.

PURPOSE: To determine whether preoperative ankle varus or valgus deformity is associated with increased 2-year mechanical or implant-related complications following primary TAA.

STUDY

DESIGN

Retrospective cohort study using a national clinical database.

METHODS

A retrospective analysis was conducted using the TriNetX Research Network, identifying patients who underwent primary TAA. Separate matched comparisons were performed for patients with preoperative ankle varus deformity versus no varus, and for valgus deformity versus no valgus. Two-year outcomes included mechanical complications, periprosthetic joint infection, implant-related pain, revision surgery, arthrodesis, and subsequent total knee arthroplasty (TKA). Relative risks (RR) with 95% confidence intervals were calculated.

RESULTS

Among 870 patients with varus deformity and 856 with valgus deformity, varus alignment was not associated with significant differences in any 2-year outcomes. In contrast, ankle valgus deformity was associated with increased risks of mechanical complications (5.02% vs 1.52%, RR 3.3, p < 0.001), implant pain (8.88% vs 4.79%, RR 1.85, p < 0.001), revision (6.19% vs 3.04%, RR 2.04, p = 0.002), arthrodesis (3.97% vs 2.22%, RR 1.79, p = 0.036), and subsequent TKA (7.86% vs 4.10%, RR 1.92, p = 0.004).

CONCLUSIONS

Preoperative ankle valgus deformity was strongly associated with higher 2-year risks of mechanical complications following TAA, whereas varus deformity was not. Recognition of valgus alignment is important when counseling patients and planning TAA.